In addition to IDAS LPS filters from Hutech (in this post) SkySlab has used Astronomik CLS light pollution filters. SkySlab’s site does not necessarily need a light pollution filter (yet!) but it has the excellent effect of colour-correcting images. Here’s the link: http://www.optcorp.com/ak-cls-t-cls-light-pollution-filter-t-threads.html It looks like this: I have read posts saying that a 3mm […]